A Kiss Is Not a Kiss

Kiss & Tell
President Barack Obama kisses First Lady Michelle Obama for the Kiss Cam while attending the U.S. Men's Olympic basketball team's game against Brazil at the Verizon Center in Washington, D.C., July 16, 2012. Pete Souza/White House/Handout

Leave it to a scientist to think anyone has to explain the importance of kissing.

A recent study confirms what most of us already know: Kissing is a great way to find and keep that special someone, but it also establishes how puckering up may be essential to the survival of the species. To say nothing of Hollywood movies.

"Kissing in human sexual relationships is incredibly prevalent in various forms across just about every society and culture," says Rafael Wlodarski, an Oxford University researcher who carried out the research. "And we are still not exactly sure why it is so widespread or what purpose it serves."

Wlodarski conducted the study (in which more than 900 adults were questioned) with the aid of Oxford psychologist Professor Robin Dunbar. The team asked subjects how important they believed kissing to be in assessing a partner's genetic fitness; how important kissing was to initiating sexual arousal; and to what extent kissing helped sustain a romantic relationship.

Readers of Jane Austen will be shocked to learn that good-looking people enjoy much more selection when it comes to choosing a partner. Winners of the genetic lottery tend to value kissing more than their less-attractive counterparts, the researchers found; they also had more casual encounters, not surprisingly. This suggests that kissing is, in part, a means of testing a partner's potential: The more men a woman kisses, the more likely she is to be selective when it comes to Mr. Right, or Mr. Darcy. (Of course it could just be that people who are more attractive kiss more people because they can.)

Scientists routinely outline three mechanisms that help us decide with whom to mate and reproduce. Helen Fisher, an anthropologist at Rutgers University, says the first tool humans evolved was sex drive, which motivates people to try a range of partners. The next is romantic love, which pushes us to focus on one person at a time. The third is feelings of attachment, which compels us to stick around and help raise a child.

According to Fisher, kissing may play a crucial role in all three. "Hooking up may have evolved as a fast-acting biological strategy for mate assessment," she said at a recent conference. "Men like sloppier kisses with more open mouths and more tongue movement. The hypothesis is they're trying to get small traces of estrogen to see where the woman is in her menstrual cycle to indicate the state of her fertility."

Experts have found that kissing sends unconscious signals to each busser regarding the other's oral health, dietary habits, and overall levels of hygiene - key metrics in deciding whether to invest their metabolic resources in the time-consuming escalation to sex.

While the Oxford study found that kissing was indeed important in beginning and sustaining a relationship, "there was little evidence that arousal is an important driver for why we kiss," according to the university's press release, "although it could well be a consequence of kissing." You think?